A Reliable Communication Model Based on IEEE802.15.4 for WSANs in Smart Grids DOI: http://dx.doi.org/10.5772/intechopen.84288

In order to describe the performance of WSANs, several analytical models are introduced in the literature. Some of these models are complicated enough not to be able to be implemented. On the other hand, some others suffer from their low precision due to simplifying and ignoring some parameters such as retransmission and buffer.

Most significantly, a vast majority of the models reach a consensus on using Poisson traffic pattern as the distribution of network input traffic [13–17]. However, delving further into the issue reveals that applications like remote monitoring and Smart Grid generate data with deterministic distribution. In other words, in these applications, each node produces data in a periodic pattern. To illustrate the concept, consider an AMI connected in a consumer side for monitoring and controlling. Based on AMI type and its protocol, the node sends data to the control center every second or minute which this fact shows that AMI data generation is periodic [18–23].

The main contribution of this paper is designing a novel analytical model for IEEE802.15.4 standard. The proposed model is specifically appropriate for applications in which the data is periodically generated such as in industry applications and Smart Grid. In these applications, on the one hand, packets are being produced based on a certain periodic time pattern. On the other hand, service time is always a random variable with general distribution. Therefore, service time might temporarily exceed the period time which, as an inevitable consequence, some packets might encounter a busy channel and be dropped. We solve this problem by proposing our MAC-level queue. We demonstrate that the proposed MAC-level queue not only increases the throughput, but also the direct connection between the generation (sensors) and communication packet systems is eliminated which makes the system far more stable.

Moreover, in order to enhance the proposed model, we have employed retransmission scheme, variable packet length, and saturated traffic condition.
